A motor generally includes a stator and a rotor. The rotor is mounted inside the stator, supported by the housing, and rotatable relative to the stator. The stator and/or the rotor of the motor has a winding including coils. In the motor, electric power passes through the coils to generate a magnetic field, thereby rotating the rotor. The motor, particularly a three-phase induction motor, can be applied to drive a compressor (for example, a scroll compressor) in the air conditioning or refrigeration industry. However, the size and performance of the compressor including the motor (particularly, the efficiency and the cooling performance of the motor) have generally great impact on the size, working efficiency and stability of air conditioning apparatus including the compressor. In addition, machinability and costs of components in the motor are also important factors in the motor design.
Generally, the efficiency of the motor may be improved by replacing an induction motor with a permanent magnet motor or by optimizing the motor design by using an optimization algorithm. However, it becomes difficult for such methods to further improve the efficiency of the motor after the efficiency of the motor is improved to a certain degree.
To ensure stability of the motor, those skilled in the art may normally try to improve the cooling performance of the motor. In particular, when the size of the air conditioning apparatus is limited, especially when the size of the compressor and the size of the motor therein are limited, the cooling performance of the motor may be improved by optimization of structures of the components in the motor, in order to obtain a better efficiency in taking heat away from the motor and to enable a lower temperature for the motor.
To improve the cooling performance of the motor, various solutions have been proposed by those skilled in the art. For example, an additional part such as a cooling medium baffle may be provided in the motor to facilitate cooling or heat dissipation.
However, the existing solutions for cooling improvement cannot improve, without changing the size, performance or machinability of the motor, the cooling performance to enable the motor to continuously operate in a stable status and under a high-efficiency operating condition.